What is the Role of Nodal Ratio as a Prognostic Factor for Gastric Cancer Nowadays? Comparison with New TNM Staging System and Analysis According to the Number of Resected Nodes

Abstract

Nodal ratio (NR) has been demonstrated to be an important prognostic factor in patients with gastric cancer. The aim of this study is to evaluate the prognostic role of nodal ratio comparing it with the new TNM (2010) classification. One hundred forty-two patients were submitted to potentially curative gastrectomy for cancer. Patients with low performance status underwent D1.5 lymphadenectomy, whereas the other patients underwent D2–D2.5 lymphadenectomy. Nodal staging was classified according to 2010 International Union Against Cancer/American Joint Committee on Cancer classification. Kaplan-Meier method was used to evaluate survival, stratified for nodal classes and nodal status. Total gastrectomy was performed in 39 per cent of cases and distal gastrectomy in 61 per cent. Mean number of resected nodes was 25.5. Whereas N status was strictly related to the number of resected nodes, the NR was independent from the extension of the lymphadenectomy. Overall five-year survival was 81 per cent for N0 patients, 72 per cent for N1, and 26 and 23 per cent for N2 and N3, respectively. Patients with NR0 had 81 per cent five-year survival, whereas NR1 67 per cent, NR2 51 per cent, and NR3 22 per cent. NR seems to be a simple method to predict the prognosis of patients with gastric cancer; unlike N status, it is independent from the number of resected nodes, and therefore it is particularly useful in case of inadequate lymphadenectomy.